1. Field of the Invention
The present invention relates generally to power-on mechanisms used to provide reset pulses.
2. Background Art
Many types of circuits require use of a power-on reset circuit to provide a reset pulse. This reset pulse is used to facilitate a delayed activation of some other circuit component, such as a memory cell.
One traditional power-on reset circuit comprises a resistor-capacitor (RC) low pass filter connected to a voltage supply. In this traditional reset circuit, when the voltage supply ramps up as power is provided, the ramp up of the voltage across the capacitor is delayed. Depending on the specific RC values involved, the voltage across the capacitor can increase exponentially, which in turn provides the delay. This capacitor voltage can subsequently be applied to a comparator (or an inverter gate) to convert the exponential signal to a squared pulse for increased compatibility with other aspects of the circuit.
Thus, the traditional RC circuit might be suitable for use as a power-on circuit in many respects. However, the large values typically required of the resistor and the capacitor make most of the traditional RC circuits so physically large, that integration into integrated circuits (ICs) is impractical. Therefore, if integration of the power-on reset circuit into an IC is desired, the traditional RC power-on circuit design will be inadequate.
What is needed, therefore, is a method and system for providing a reset circuit suitable for integration onto an IC.